Opening statements are underway in a deadly shooting that happen at NAU.

Copyright 2017 Scripps Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

FLAGSTAFF, AZ - It was an emotional day inside the Coconino Court House as jury selection was finalized and arguments began in the Northern Arizona University shooting case.

Steven Jones, 20, is accused of first-degree murder and six counts of aggravated assault for allegedly shooting and killing Colin Brough and wounding three others on Oct. 9, 2015.

Jones has plead not guilty and has maintained that he acted in self-defense when he fired his gun that night at NAU. He told police in 2015 that several people approached him and two of his friends; a fight broke out and Jones claimed he was punched. In court on Wednesday, the state argued that after Jones was punched he walked more than 150 feet to his car where his gun was located. Prosecutors claim that Jones then walked another 90 feet to the group of students with his gun.

Meanwhile, Jones’ lawyers argued that Jones had to defend himself from Brough when he returned to the scene. Jones’ attorney Josh Davidson said in his opening remarks that the medical examiner’s report will prove Brough lunged at Jones forcing him to pull the trigger.

The jury panel is comprised of 14 jurors. It includes seven men and seven women.

The state will be calling approximately 35 witnesses to the stand, including some of the surviving victims. The trial is expected to last until May.

Copyright 2017 Scripps Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.